mohamed abdillahi - Academia.edu (original) (raw)

Papers by mohamed abdillahi

In May 2000, an unusual fixed airways obstruction in eight workers of a microwave popcorn plant i... more In May 2000, an unusual fixed airways obstruction in eight workers of a microwave popcorn plant in Missouri brought up national attention. However, the cause of this lung disease, resembling bronchiolitis obliterans, was due to exposure to the predominant vapor of diacetyl that gives the smell and flavor of butter to popcorn. Following that, many more cases of lung disease were reported in 2002-2006 which resulted in passing the Popcorn Workers Lung Disease Prevention Act in 2007. Diacetyl can be made in through fermentation, and a copper catalyst. It gives the butter flavor and taste to some foods such as popcorn, dairy products, coffee, and alcoholic beverages. Diacetyl can be a product from decomposition of methyl ethyl ketone. The companies primarily synthesize diacetyl to use it as a food additive. A large number of workers are exposed to diacetyl, as a result of its production and usage in the food industries. NIOSH performed an experiment in the 1980's and found that thousands of workers were potentially exposed to diacetyl in the United States. Exposure to diacetyl may occur through inhalation of butter flavoring vapors, ingestion of foods and drinking water containing diacetyl, and dermal contact with consumer products containing this compound. These exposures may pose some significant health risks to the related workers particularly for those working directly with the substance. Due to its relatively low vapor pressure, diacetyl is an airborne chemical in butter-flavoring for popcorn. Studies showed that diacetyl inhalation causes some lung problems in the workers who mix oil and butter flavoring at the plant depending on length of exposure. These issues can be mentioned as severe injury of the epithelium airway, shortness of breath, and cough as a result of manufacturing buttered popcorn. The prominent upper respiratory tract issues including sensory and nasal tissue irritation and inflammation were considered. Testing of rats for acute and subchronic studies indicate the upper respiratory tract to be a significant target for symptoms due to cytotoxic effects of diacetyl vapor. Workers chronic exposure to diacetyl may result to a nonreversible lung disease called bronchiolitis obliterations. Those who work in facilities with open containers of artificial butter flavoring are more susceptible to diacetyl exposure. Smokers and children if exposed to the vapor would be affected more when considering their forced expiratory volume.

PLANT ARCHIVES, 2021

In one stage of mankind's struggle to keep pace with ever increasing demand of food due to accele... more In one stage of mankind's struggle to keep pace with ever increasing demand of food due to accelerating world population, chemical fertilizers contributed enormously to produce sufficient food products. However, a stagnation in the crop productivity along with decreasing soil fertility status and environmental pollution due to continuous, excessive, and imbalanced use of chemical fertilizers. In this scenario, plant growth promoting rhizobacteria (PGPR) become a natural choice as an alternative to the fertilizer to alleviate excessive consumption of fertilizers because PGPR not only promote nutrient availability to plants as biofertilizers but also performin several ways to stimulate plant growth and hence their productivity. In this review, an attempt has been made to highlight the main activities of PGPR in soil and plants, and to analyse their mode of actions from chemistry point of view.

The Asal-rift geothermal field is the most active structure which is the westward prolongation of... more The Asal-rift geothermal field is the most active structure which is the westward prolongation of the Gulf of Aden. Almost all the region is covered by volcanic rocks and thermal manifestations with same sediment deposit. All the fault system is oriented NW-SE. Six deep wells were drilled between 1975-88 and one shallow well (Glc1) was drilled in 2016. The maximum depth for all the wells is 2105m with a maximum temperature of 359°C. This study is mainly focused on sub-surface description of hydrothermal alteration of wells Asal 3, 4, 5 and Glc 1. The wells were drilled directionally on the top of Asal-rift. The lithology unit encountered succeed from youngest to oldest; 1) Asal series less 1Ma consisting of porphyritic basalt and hyaloclastite; 2) Pleistocene sediment 3)Afar stratoid, mainly consisting of rhyolite in the upper part ranging between 4 to 1Ma; 4) Pliocene clays 5) Dalha basalt series, this unit consists of a sequence of lava flows, with intercalation of trachytes and d...

Cette these est composee de deux parties: une premiere partie traite le probleme de changement de... more Cette these est composee de deux parties: une premiere partie traite le probleme de changement de regime et une deuxieme partie concerne le processusautoregressif a seuil dont les innovations ne sont pas independantes. Toutefois, ces deux domaines de la statistique et des probabilites se rejoignent dans la litterature et donc dans mon projet de recherche. Dans la premiere partie, nous etudions le probleme de changements deregime. Il existe plusieurs methodes pour la detection de ruptures mais les principales methodes sont : la methode de moindres carres penalises (PLS)et la methode de derivee filtree (FD) introduit par Basseville et Nikirov. D’autres methodes existent telles que la methode Bayesienne de changementde points. Nous avons valide la nouvelle methode de derivee filtree et taux de fausses decouvertes (FDqV) sur des donnees reelles (des donnees du vent sur des eoliennes et des donnees du battement du coeur). Bien naturellement, nous avons donne une extension de la methode F...

African Journal of Primary Health Care & Family Medicine, 2021

World Journal of Engineering and Technology, 2020

In this study, nineteen different brands of bottled mineral waters (7 brands local and 12 brands ... more In this study, nineteen different brands of bottled mineral waters (7 brands local and 12 brands imported) were collected from supermarkets and independent food stores throughout Djibouti. The chemical composition mentioned on the labels of the nineteen bottled mineral waters has made the subject of a first verification by Ionic Balance Error (IBE). It was found out of the nineteen brands selected, 12 brands (2 brands local and 10 brands imported) had acceptable charge balance error. Correlation Analysis (CA), Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were used to analyze the data collected from the labels of bottled water. The obtained results showed that the 12 brands of studied waters can be grouped in 4 distinct classes with similar chemical characteristics. Two local and one imported brands have the same chemical composition but marketed under different names. It was observed that the chemical content local water brands were within the normal range prescribed by both WHO and USEPA except five imported water brands that have concentration values Ca, HCO 3 , Mg and SO 4 beyond acceptable standards. Total hardness values classified most of the studied brands from moderate to very hard water.

Lex Social: Revista de Derechos Sociales, 2020

Con el crecimiento de las migraciones de estas últimas décadas, la mujer inmigrante originaria de... more Con el crecimiento de las migraciones de estas últimas décadas, la mujer inmigrante originaria de los países del Sur ha entrado en el mundo laboral. Como el hombre, las oportunidades laborales motivan muchas mujeres subsaharianas en emprender proyectos personales o/y colectivos de migración hacia otros contextos socioeconómicos. Durante mucho tiempo su presencia y su protagonismo en los movimientos migratorios han dejado indiferentes a investigadoras e investigadores en ciencias sociales las/los cuales reflejaban en sus estudios únicamente las migraciones desde la perspectiva del hombre, es decir masculina. Que sigua su marido o que vaya sola, tener un empleo es también una prioridad. Se la han mantenido en la invisibilidad laboral y social. El presente trabajo se centra en primer lugar sobre la discriminación que sufren las mujeres inmigrantes subsaharianas residentes en la Región de Murcia. En segundo lugar, trata la migración de estas mujeres en las últimas décadas fuera de sus p...

Http Www Theses Fr, Dec 15, 2014

International Journal of Statistics and Probability, 2013

Let X = (X 1 , X 2 ,. .. , X n) be a time series, that is a sequence of random variable indexed b... more Let X = (X 1 , X 2 ,. .. , X n) be a time series, that is a sequence of random variable indexed by the time t = 1, 2,. .. , n. We assume the existence of a segmentation τ = (τ 1 , τ 2 ,. .. , τ n) such that X i is a family of independent identically distributed (i.i.d) random variable for i ∈ (τ k , τ k + 1], and k = 0,. .. , K where by convention τ o and τ K+1 = N. In the literature, it exist two main kinds of change points detections: The change points on-line and the change points off-line. In this work, we consider only the change point analysis (off-line), when number of change points is unknown. The result obtained is based on Filtered Derivative method where we use a second step based on False Discovery Rate. We compare numerically this new method with the Filtered Derivative with p-Value.

International Journal of Statistics and Probability, 2014

Let X = (X 1 , X 2 ,. .. , X N) be a time series. That is a sequence random variable indexed by t... more Let X = (X 1 , X 2 ,. .. , X N) be a time series. That is a sequence random variable indexed by the time t = (1, 2,. .. , N), we suppose that the parameters of X are piecewise constant. In other words, it exists a subdivision τ = (τ 1 < τ 2 <. .. < τ K) such that X i is a family of independent and identically distributed (i.i.d) random variables for i ∈ (τ k , τ k+1 ], and k = 0, 1,. .. , K where by convention τ o = 0 and τ K+1 = N. The preceding works such that (Bertrand, 2000) control the probability of false alarms for minimizing the probability of type I error of change point analysis. The novelty in this work is to control the number of false alarms. We give an bound of number of false alarms and the necessary condition for number of no detection. In other hand, we know the filtered derivative (Basseville & Nikirov, 1993) depends the parameters such that the threshold and the window, we give in order to choose the optimal parameters. We compare the results of Filtered Derivative optimized parameters and the Penalized Square Error methods in particulary the adaptive method of (Lavielle & Teyssière, 2006).

Zeolites, 1996

MFI-type zeolites were synthesized by the rapid crystallization method in 2 h. The synthesis para... more MFI-type zeolites were synthesized by the rapid crystallization method in 2 h. The synthesis parameters were studied briefly using a statistical method, and the pH of the initial hydrogel was found to be the most critical parameter under the synthesis conditions used and the crystallization time constrain. The physicochemical properties of the zeolite products were studied and found to have some advantages over conventionally synthesized zeolites. The thermal stability was found to decrease with increasing SVAI ratio contrary to what was widely accepted. It was speculated that high concentrations of defect sites exaggerated by the rapid crystallization time may be responsible for the trend of thermal stability.

Journal of the Folklore Institute, 1967

... 200 MOHAMED FARAH ABDILLAHI AND BW ANDRZEJEWSKI Oh Hodan 'Abdi, why did I not break ... more ... 200 MOHAMED FARAH ABDILLAHI AND BW ANDRZEJEWSKI Oh Hodan 'Abdi, why did I not break away ... 204 MOHAMED FARAH ABDILLAHI AND BW ANDRZEJEWSKI ... the same sources as those of such renowned Somali poets as Raage Ugaas, Mahammed 'Abdille Hasan ...

The Analyst, 1995

Raney nickel, Houston Atlas and gas chromatographic-flame photometric detection (GC-F&amp... more Raney nickel, Houston Atlas and gas chromatographic-flame photometric detection (GC-F&amp;amp;amp;amp;#x27;PD) methods were applied to the determination of trace amounts of sulfur in naphthas. The parameters investigated included the linearity, detection limits and the repeatability of ...

The Analyst, 1986

A helium microwave induced plasma is utilised for the determination of bromide. The bromide sampl... more A helium microwave induced plasma is utilised for the determination of bromide. The bromide sample solution is either introduced into an oxidation - generation mixture of potassium dichromate - sulphuric acid, or is vaporised electrothermally and then swept into the helium plasma. ...

Journal of Applied Polymer Science, 2007

Applied Spectroscopy, 1993

Trace level quantities of some nonmetallic elements are determined by coupling graphite rod elect... more Trace level quantities of some nonmetallic elements are determined by coupling graphite rod electrothermal vaporization with a helium microwave-induced plasma. Microliter liquid samples of chlorides, bromides, iodides, sulfides, and ammonium nitrogen have been introduced into a grooved graphite rod, where they were dried, ashed, and vaporized into the plasma. The analytical performance of the GRV/He-MIP was found to be an excellent excitation source for dry analyte vapors. The graphite rod vaporization device is well suited for sample introduction for a lowpower microwave-induced plasma. Analytical calibration curves were obtained that have linearities between 2.5 to 5 orders of magnitude. Detection limits of the technique for 10- μL aqueous sample solutions are reported in the lower nanogram region. The common anions and cations did not show significant interference effects on the determination of traces of these nonmetals.

Applied Catalysis A: General, 1992

High-silica zeolite (silicalite) was modified with Ba resulting in reduced acid strength of the c... more High-silica zeolite (silicalite) was modified with Ba resulting in reduced acid strength of the catalyst and better performance when compared with ZSM-5 and fresh silicalite in converting MeOH to alkenes. Various concns. of Ba were ionexchanged and impregnated to achieve the optimum loading of the modifier. The fresh and the modified zeolites were fully characterized by x-ray diffraction, SEM, TGA, DTA, as well as by surface area, chem. and other analyses. Ba silicalite has a lowered coke deposition and an improved active life when ion exchanged. The reverse was obsd. in the case of impregnation.

Applied Catalysis A: General, 1997

Catalytic conversion of methanol to light alkenes was investigated using a high silica zeolite of... more Catalytic conversion of methanol to light alkenes was investigated using a high silica zeolite of the pentasil type MFI structure. The reaction was carried out in a fixed bed reaction setup at 400°C, WHSV =4 h-i, pressure of 1 atm, and MeOH]N 2 (wt) ratio of 2.78. The silicalite zeolite (UC-S-115) was modified by impregnation with metal nitrates of Ag, Ca, Cd, Cu, Ga, In, La and Sr to study their effects on the activity and selectivity of the catalyst to lower alkenes. Incorporation of La and Ag led to an improvement in light alkene selectivity of the silicalite by 18% and 14% respectively. This was attributed to enhanced shape selectivity of the silicalite resulting from reduction of the apparent pore size of zeolite channels. The active life-on-stream was slightly decreased due to coke deposition. A non-rigorous least square fit of the catalyst life exhibited an exponential decay as a function of coke deposition rate above 0.17 wt% h-1. Below 0.17 wt% h-l however, the active life-on-stream becomes insensitive to the rate of coking and is probably determined largely by catalyst intrinsic properties.